The climate system has undergone several rapid and large magnitude events in the period from last glacial maximum (LGM) to present day. Two of these key events occur between 15 and 14 cal. kyr BP: the warming of the northern Atlantic region (the Bolling-A llerod warm interval) and a rapid sea-level rise of around 25m in 1 kyr, meltwater pulse IA (mwp-IA). Recent sea-level modelling studies show that equatorial data are more compatible with a melt-source for mwp-IA that includes a dominant Antarctic component [Clark et al., Science, 295, 2438 2002] which could also explain the onset of the Bolling-Allerod [Weaver et al., Science 299, 5613, 2003] whereas, a dominant Laurentide source could result in the shut down of North Atlantic Deep Water formation and a major climatic cooling [Clark et al., Paleoceanography, 11, 5, 1996].
The primary aim of this proposed research is to test the feasibility of rapid and large-magnitude deglaciation of the Antarctic ice sheet and consider the possibility of Antarctic melting as a trigger for the Bolling-Allerod warm interval. This will be investigated by utilising both a realistic thermomechanically coupled Antarctic ice sheet model [e.g. Huybrechts, Quaternary Science Reviews, 21, 2002] and an algorithm for predicting glaciation induced sea-level changes [Milne, AGU Monograph Geodynamic Series, 29, 2002]. The effect of climatic and sea level forcings will both be considered as possible triggers to initiate earlier melting of the Antarctic ice sheet.
A secondary aim of the research will be to construct an improved model of Antarctic ice sheet deglaciation by using field evidence of ice extent and observations of sea-level changes and crustal deformation from GPS data. The results of this study would have far-reaching impact o n a broad range of research areas (e.g. glaciology, oceanography, glacial geology, glacial isostatic adjustment, sea-level change).
Call for proposal
See other projects for this call